Funding & Acknowledgements

The data used in this analysis is from the Export Standardized Tables in the SEACAR Data Discovery Interface (DDI). Documents and information available through the SEACAR DDI are owned by the data provider(s) and users are expected to provide appropriate credit following accepted citation formats. Users are encouraged to access data to maximize utilization of gained knowledge, reducing redundant research and facilitating partnerships and scientific innovation.

With respect to documents and information available from SEACAR DDI, neither the State of Florida nor the Florida Department of Environmental Protection makes any warranty, expressed or implied, including the warranties of merchantability and fitness for a particular purpose arising out of the use or inability to use the data, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights.

This report was funded in part, through a grant agreement from the Florida Department of Environmental Protection, Florida Coastal Management Program, by a grant provided by the Office for Coastal Management under the Coastal Zone Management Act of 1972, as amended, National Oceanic and Atmospheric Administration. The views, statements, findings, conclusions and recommendations expressed herein are those of the author(s) and do not necessarily reflect the views of the State of Florida, NOAA or any of their sub agencies.

Published: 2025-05-22

Threshold Filtering

Threshold filters, following the guidance of Florida Department of Environmental Protection’s (FDEP) Division of Environmental Assessment and Restoration (DEAR) are used to exclude specific results values from the SEACAR Analysis. Based on the threshold filters, Quality Assurance / Quality Control (QAQC) Flags are inserted into the SEACAR_QAQCFlagCode and SEACAR_QAQC_Description columns of the export data. The Include column indicates whether the QAQC Flag will also indicate that data are excluded from analysis. No data are excluded from the data export, but the analysis scripts can use the Include column to exclude data (1 to include, 0 to exclude).

Continuous Water Quality threshold values
Parameter Name Units Low Threshold High Threshold
Dissolved Oxygen mg/L -0.000001 50
Dissolved Oxygen Saturation % -0.000001 500
Salinity ppt -0.000001 70
Turbidity NTU -0.000001 4000
Water Temperature Degrees C -5.000000 45
pH None 2.000000 14
Discrete Water Quality threshold values
Parameter Name Units Low Threshold High Threshold
Ammonia, Un-ionized (NH3) mg/L - -
Ammonium, Filtered (NH4) mg/L - -
Chlorophyll a, Corrected for Pheophytin ug/L - -
Chlorophyll a, Uncorrected for Pheophytin ug/L - -
Colored Dissolved Organic Matter PCU - -
Dissolved Oxygen mg/L -0.000001 25
Dissolved Oxygen Saturation % -0.000001 310
Fluorescent Dissolved Organic Matter QSE - -
Light Extinction Coefficient m^-1 - -
NO2+3, Filtered mg/L - -
Nitrate (NO3) mg/L - -
Nitrite (NO2) mg/L - -
Nitrogen, organic mg/L - -
Phosphate, Filtered (PO4) mg/L - -
Salinity ppt -0.000001 70
Secchi Depth m 0.000001 50
Specific Conductivity mS/cm 0.005000 100
Total Kjeldahl Nitrogen mg/L - -
Total Nitrogen mg/L - -
Total Nitrogen mg/L - -
Total Phosphorus mg/L - -
Total Suspended Solids mg/L - -
Turbidity NTU - -
Water Temperature Degrees C 3.000000 40
pH None 2.000000 13
Quality Assurance Flags inserted based on threshold checks listed in Table 1 and 2
SEACAR QAQC Description Include SEACAR QAQCFlagCode
Exceeds maximum threshold 0 2Q
Below minimum threshold 0 4Q
Within threshold tolerance 1 6Q
No defined thresholds for this parameter 1 7Q

Value Qualifiers

Value qualifier codes included within the data are used to exclude certain results from the analysis. The data are retained in the data export files, but the analysis uses the Include column to filter the results.

STORET and WIN value qualifier codes

Value qualifier codes from STORET and WIN data are examined with the database and used to populate the Include column in data exports.

Value Qualifier codes excluded from analysis
Qualifier Source Value Qualifier Include MDL Description
STORET-WIN H 0 0 Value based on field kit determination; results may not be accurate
STORET-WIN J 0 0 Estimated value
STORET-WIN V 0 0 Analyte was detected at or above method detection limit
STORET-WIN Y 0 0

Discrete Water Quality Value Qualifiers

The following value qualifiers are highlighted in the Discrete Water Quality section of this report. An exception is made for Program 476 - Charlotte Harbor Estuaries Volunteer Water Quality Monitoring Network and data flagged with Value Qualifier H are included for this program only.

H - Value based on field kit determiniation; results may not be accurate. This code shall be used if a field screening test (e.g., field gas chromatograph data, immunoassay, or vendor-supplied field kit) was used to generate the value and the field kit or method has not been recognized by the Department as equivalent to laboratory methods.

I - The reported value is greater than or equal to the laboratory method detection limit but less than the laboratory practical quantitation limit.

Q - Sample held beyond the accepted holding time. This code shall be used if the value is derived from a sample that was prepared or analyzed after the approved holding time restrictions for sample preparation or analysis.

S - Secchi disk visible to bottom of waterbody. The value reported is the depth of the waterbody at the location of the Secchi disk measurement.

U - Indicates that the compound was analyzed for but not detected. This symbol shall be used to indicate that the specified component was not detected. The value associated with the qualifier shall be the laboratory method detection limit. Unless requested by the client, less than the method detection limit values shall not be reported

Systemwide Monitoring Program (SWMP) value qualifier codes

Value qualifier codes from the SWMP continuous program are examined with the database and used to populate the Include column in data exports. SWMP Qualifier Codes are indicated by QualifierSource=SWMP.

SWMP Value Qualifier codes
Qualifier Source Value Qualifier Include Description
SWMP -1 1 Optional parameter not collected
SWMP -2 0 Missing data
SWMP -3 0 Data rejected due to QA/QC
SWMP -4 0 Outside low sensor range
SWMP -5 0 Outside high sensor range
SWMP 0 1 Passed initial QA/QC checks
SWMP 1 0 Suspect data
SWMP 2 1 Reserved for future use
SWMP 3 1
SWMP 4 1 Historical: Pre-auto QA/QC
SWMP 5 1 Corrected data

Water Column

The water column habitat extends from the water’s surface to the bottom sediments, and it’s where fish, dolphins, crabs and people swim! So much life makes its home in the water column that the health of marine and coastal ecosystems, as well as human economies, depend on the condition of this vulnerable habitat. Local patterns of rainfall, temperature, winds and currents can rapidly change the condition of the water column, while global influences such as El Niño/La Niña, large-scale fluctuation in sea temperatures and climate change can have long-term effects. Inputs from the prosperity of our day-to-day lives including farming, mining and forestry, and emissions from power generation, automobiles and water treatment can also alter the health of the water column. Acting alone or together, each input can have complex and lasting effects on habitats and ecosystems.


SEACAR evaluates water column health with several essential parameters. These include nutrient surveys of nitrogen and phosphorus, and water quality assessments of salinity, dissolved oxygen, pH, and water temperature. Water clarity is evaluated with Secchi depth, turbidity, levels of chlorophyll a, total suspended solids, and colored dissolved organic matter. Additionally, the richness of nekton is indicated by the abundance of free-swimming fishes and macroinvertebrates like crabs and shrimps.

Seasonal Kendall-Tau Analysis

Indicators must have a minimum of five to ten years, depending on the habitat, of data within the geographic range of the analysis to be included in the analysis. Ten years of data are required for discrete parameters, and five years of data are required for continuous parameters. If there are insufficient years of data, the number of years of data available will be noted and labeled as “insufficient data to conduct analysis”. Further, for the preferred Seasonal Kendall-Tau test, there must be data from at least two months in common across at least two consecutive years within the RCP managed area being analyzed. Values that pass both of these tests will be included in the analysis and be labeled as Use_In_Analysis = TRUE. Any that fail either test will be excluded from the analyses and labeled as Use_In_Analysis = FALSE. The points for all Water Column plots displayed in this section are monthly averages. Trend significance will be denoted as “Significant Trend” (when p < 0.05), or “Non-significant Trend” (when p >= 0.05). Any parameters with insufficient data to perform Seasonal Kendall-Tau test will have their monthly averages plotted without a corresponding trend line.

Water Quality - Discrete

The following files were used in the discrete analysis:

  • Combined_WQ_WC_NUT_Chlorophyll_a_corrected_for_pheophytin-2025-Mar-06.txt

  • Combined_WQ_WC_NUT_Chlorophyll_a_uncorrected_for_pheophytin-2025-Mar-06.txt

  • Combined_WQ_WC_NUT_Colored_dissolved_organic_matter_CDOM-2025-Mar-06.txt

  • Combined_WQ_WC_NUT_Dissolved_Oxygen-2025-Mar-06.txt

  • Combined_WQ_WC_NUT_Dissolved_Oxygen_Saturation-2025-Mar-06.txt

  • Combined_WQ_WC_NUT_pH-2025-Mar-06.txt

  • Combined_WQ_WC_NUT_Salinity-2025-Mar-06.txt

  • Combined_WQ_WC_NUT_Secchi_Depth-2025-Mar-06.txt

  • Combined_WQ_WC_NUT_Total_Nitrogen-2025-Mar-06.txt

  • Combined_WQ_WC_NUT_Total_Phosphorus-2025-Mar-06.txt

  • Combined_WQ_WC_NUT_Total_Suspended_Solids_TSS-2025-Mar-06.txt

  • Combined_WQ_WC_NUT_Turbidity-2025-Mar-06.txt

  • Combined_WQ_WC_NUT_Water_Temperature-2025-Mar-06.txt

Chlorophyll a, Corrected for Pheophytin - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average levels of chlorophyll a, corrected for pheophytin, over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only laboratory-analyzed chlorophyll a (triangles) is included in the plot.
Scatter plot of monthly average levels of chlorophyll a, corrected for pheophytin, over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only laboratory-analyzed chlorophyll a (triangles) is included in the plot.
Seasonal Kendall-Tau Trend Analysis for Chlorophyll a, Corrected for Pheophytin
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Lab Significantly increasing trend 2048 17 2004 - 2024 0.62 0.2827 0.2309 0.0411 0

Monthly average chlorophyll a, corrected for pheophytin, increased by 0.04 µg/L per year, indicating a decrease in water clarity.

Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Chlorophyll a, Corrected for Pheophytin
ProgramID N_Data YearMin YearMax
5002 1943 2004 2024
514 198 2018 2024

Program names:

514 - Florida LAKEWATCH Program1
5002 - Florida STORET / WIN2

Chlorophyll a, Uncorrected for Pheophytin - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average levels of chlorophyll a, uncorrected for pheophytin, over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only laboratory-analyzed chlorophyll a (triangles) is included in the plot.
Scatter plot of monthly average levels of chlorophyll a, uncorrected for pheophytin, over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only laboratory-analyzed chlorophyll a (triangles) is included in the plot.
Seasonal Kendall-Tau Trend Analysis for Chlorophyll a, Uncorrected for Pheophytin
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Lab No significant trend 21249 36 1989 - 2024 0.2973 0.0554 0.4152 0.0022 0.1261

Chlorophyll a, uncorrected for pheophytin, showed no detectable trend between 1989 and 2024.

Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Chlorophyll a, Uncorrected for Pheophytin
ProgramID N_Data YearMin YearMax
297 16110 1995 2023
3 4011 1998 2024
514 2819 1998 2024
509 1418 1989 2008
5002 987 2001 2024
60 345 1993 2016
103 154 2000 2021
118 28 2000 2010
115 28 2000 2004

Program names:

3 - Atlantic Oceanographic and Meteorological Laboratory (AOML) South Florida Program Synoptic Shipboard Surveys3
60 - Southeast Area Monitoring and Assessment Program (SEAMAP) - Gulf of Mexico Fall & Summer Shrimp/Groundfish Survey4
103 - EPA STOrage and RETrieval Data Warehouse (STORET)/WQX5
115 - Environmental Monitoring Assessment Program6
118 - National Aquatic Resource Surveys, National Coastal Condition Assessment7
297 - Florida Keys National Marine Sanctuary Water Quality Monitoring Project8
509 - SERC Water Quality Monitoring Network9
514 - Florida LAKEWATCH Program1
5002 - Florida STORET / WIN2

Colored Dissolved Organic Matter - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average colored dissolved organic matter (CDOM) over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only laboratory-analyzed CDOM (triangles) is included in the plot.
Scatter plot of monthly average colored dissolved organic matter (CDOM) over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only laboratory-analyzed CDOM (triangles) is included in the plot.
Seasonal Kendall-Tau Trend Analysis for Colored Dissolved Organic Matter
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Lab Significantly increasing trend 1025 24 2001 - 2024 6 0.2457 5.4354 0.1048 0.0003

Monthly average colored dissolved organic matter increased by 0.1 PCU per year, indicating a decrease in water clarity.

Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Colored Dissolved Organic Matter
ProgramID N_Data YearMin YearMax
514 1025 2001 2024

Program names:

514 - Florida LAKEWATCH Program1

Dissolved Oxygen - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average dissolved oxygen over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only dissolved oxygen values measured in the field (circles) are included in the plot.
Scatter plot of monthly average dissolved oxygen over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only dissolved oxygen values measured in the field (circles) are included in the plot.
Seasonal Kendall-Tau Trend Analysis for Dissolved Oxygen
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Field Significantly decreasing trend 47232 41 1970 - 2024 6.3 -0.0912 6.6235 -0.0063 0.0051

Monthly average dissolved oxygen decreased by 0.01 mg/L per year.

Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Dissolved Oxygen
ProgramID N_Data YearMin YearMax
297 32169 1995 2023
5002 5155 2003 2024
509 2701 1989 2008
69 1743 1997 2022
60 1592 1993 2016
95 1560 1994 2018
4049 1024 2006 2023
103 601 1970 2021
3000 377 2015 2018
118 104 2000 2021
899 93 2014 2015
115 89 2000 2004
4057 59 2015 2018
102 42 1996 2000

Program names:

60 - Southeast Area Monitoring and Assessment Program (SEAMAP) - Gulf of Mexico Fall & Summer Shrimp/Groundfish Survey4
69 - Fisheries-Independent Monitoring (FIM) Program10
95 - Harmful Algal Bloom Marine Observation Network11
102 - National Status and Trends Mussel Watch12
103 - EPA STOrage and RETrieval Data Warehouse (STORET)/WQX5
115 - Environmental Monitoring Assessment Program6
118 - National Aquatic Resource Surveys, National Coastal Condition Assessment7
297 - Florida Keys National Marine Sanctuary Water Quality Monitoring Project8
509 - SERC Water Quality Monitoring Network9
899 - USGS Coral Reef Ecosystem Studies (CREST) Project13
3000 - Florida Keys Water Watch14
4049 - The South Florida Fisheries Habitat Assessment Program (FHAP)15
4057 - Biscayne Bay Water Watch16
5002 - Florida STORET / WIN2

Dissolved Oxygen Saturation - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average dissolved oxygen saturation over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only dissolved oxygen saturation values measured in the field (circles) are included in the plot.
Scatter plot of monthly average dissolved oxygen saturation over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only dissolved oxygen saturation values measured in the field (circles) are included in the plot.
Seasonal Kendall-Tau Trend Analysis for Dissolved Oxygen Saturation
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Field Significantly increasing trend 29283 30 1995 - 2024 94.7731 0.1922 91.9441 0.18 0

Monthly average dissolved oxygen saturation increased by 0.18% per year.

Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Dissolved Oxygen Saturation
ProgramID N_Data YearMin YearMax
297 25419 1995 2020
5002 3907 2009 2024
102 18 1996 1996
95 1 2017 2017

Program names:

95 - Harmful Algal Bloom Marine Observation Network11
102 - National Status and Trends Mussel Watch12
297 - Florida Keys National Marine Sanctuary Water Quality Monitoring Project8
5002 - Florida STORET / WIN2

pH - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average pH over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only pH values measured in the field (circles) are included in the plot.
Scatter plot of monthly average pH over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only pH values measured in the field (circles) are included in the plot.
Seasonal Kendall-Tau Trend Analysis for pH
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Field Significantly decreasing trend 9785 30 1970 - 2024 8.04 -0.167 8.1609 -0.0038 0

Monthly average pH decreased by less than 0.01 pH units per year.

Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for pH
ProgramID N_Data YearMin YearMax
5002 5287 2003 2024
69 1733 1997 2022
4049 1103 2005 2023
509 545 2002 2008
3000 377 2015 2018
3 287 2009 2012
95 142 1994 2018
297 114 2003 2011
115 89 2000 2004
899 88 2014 2015
103 86 1970 2021
4057 59 2015 2018

Program names:

3 - Atlantic Oceanographic and Meteorological Laboratory (AOML) South Florida Program Synoptic Shipboard Surveys3
69 - Fisheries-Independent Monitoring (FIM) Program10
95 - Harmful Algal Bloom Marine Observation Network11
103 - EPA STOrage and RETrieval Data Warehouse (STORET)/WQX5
115 - Environmental Monitoring Assessment Program6
297 - Florida Keys National Marine Sanctuary Water Quality Monitoring Project8
509 - SERC Water Quality Monitoring Network9
899 - USGS Coral Reef Ecosystem Studies (CREST) Project13
3000 - Florida Keys Water Watch14
4049 - The South Florida Fisheries Habitat Assessment Program (FHAP)15
4057 - Biscayne Bay Water Watch16
5002 - Florida STORET / WIN2

Salinity - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average salinity over time. If the time series included ten or more years of discrete observations, significant (blue) or non-significant (magenta) trend lines are also shown. Discrete salinity values derived from grab samples analyzed in the field (circles) or the laboratory (triangles) are both included in the plot.
Scatter plot of monthly average salinity over time. If the time series included ten or more years of discrete observations, significant (blue) or non-significant (magenta) trend lines are also shown. Discrete salinity values derived from grab samples analyzed in the field (circles) or the laboratory (triangles) are both included in the plot.
Seasonal Kendall-Tau Trend Analysis for Salinity
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
All No significant trend 54590 47 1955 - 2024 36.19 0.0275 34.8062 0.0072 0.4344

Salinity showed no detectable trend between 1955 and 2024.

Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Salinity
ProgramID N_Data YearMin YearMax
297 31841 1995 2023
5002 5291 2003 2024
3 4343 1998 2024
509 2581 1989 2008
965 2317 2005 2011
95 1889 1955 2018
69 1741 1997 2022
60 1524 1993 2016
4049 1168 2005 2023
62 1142 1993 2019
3000 379 2015 2018
118 109 2015 2021
115 89 2000 2004
899 82 2014 2015
102 60 1996 2000
4057 59 2015 2018

Program names:

3 - Atlantic Oceanographic and Meteorological Laboratory (AOML) South Florida Program Synoptic Shipboard Surveys3
60 - Southeast Area Monitoring and Assessment Program (SEAMAP) - Gulf of Mexico Fall & Summer Shrimp/Groundfish Survey4
62 - Southeast Area Monitoring and Assessment Program (SEAMAP) - Gulf of Mexico Reef Fish Survey17
69 - Fisheries-Independent Monitoring (FIM) Program10
95 - Harmful Algal Bloom Marine Observation Network11
102 - National Status and Trends Mussel Watch12
115 - Environmental Monitoring Assessment Program6
118 - National Aquatic Resource Surveys, National Coastal Condition Assessment7
297 - Florida Keys National Marine Sanctuary Water Quality Monitoring Project8
509 - SERC Water Quality Monitoring Network9
899 - USGS Coral Reef Ecosystem Studies (CREST) Project13
965 - South Florida Seagrass Fish and Invertebrate Assessment Network18
3000 - Florida Keys Water Watch14
4049 - The South Florida Fisheries Habitat Assessment Program (FHAP)15
4057 - Biscayne Bay Water Watch16
5002 - Florida STORET / WIN2

Secchi Depth - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average Secchi depth over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Secchi depth is only measured in the field (circles).
Scatter plot of monthly average Secchi depth over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Secchi depth is only measured in the field (circles).
Seasonal Kendall-Tau Trend Analysis for Secchi Depth
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Field No significant trend 5051 30 1993 - 2024 -2.1336 0.0036 -2.4543 0.0007 0.8805

Secchi depth showed no detectable trend between 1993 and 2024.

Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Secchi Depth
ProgramID N_Data YearMin YearMax
514 2500 1998 2024
69 1750 1997 2022
3000 373 2015 2018
5002 352 2005 2022
4049 252 2005 2023
60 37 1993 2002
115 21 2000 2004

Program names:

60 - Southeast Area Monitoring and Assessment Program (SEAMAP) - Gulf of Mexico Fall & Summer Shrimp/Groundfish Survey4
69 - Fisheries-Independent Monitoring (FIM) Program10
115 - Environmental Monitoring Assessment Program6
514 - Florida LAKEWATCH Program1
3000 - Florida Keys Water Watch14
4049 - The South Florida Fisheries Habitat Assessment Program (FHAP)15
5002 - Florida STORET / WIN2

Total Nitrogen - Discrete

Total Nitrogen Calculation:

The logic for calculated Total Nitrogen was provided by Kevin O’Donnell and colleagues at FDEP (with the help of Jay Silvanima, Watershed Monitoring Section). The following logic is used, in this order, based on the availability of specific nitrogen components.

  1. TN = TKN + NO3O2;
  2. TN = TKN + NO3 + NO2;
  3. TN = ORGN + NH4 + NO3O2;
  4. TN = ORGN + NH4 + NO2 + NO3;
  5. TN = TKN + NO3;
  6. TN = ORGN + NH4 + NO3;

Additional Information:

  • Rules for use of sample fraction:
    • Florida Department of Environmental Protection (FDEP) report that if both “Total” and “Dissolved” components are reported, only “Total” is used. If the total is not reported, then the dissolved components are used as a best available replacement.
    • Total nitrogen calculations are done using nitrogen components with the same sample fraction, nitrogen components with mixed total/dissolved sample fractions are not used. In other words, total nitrogen can be calculated when TKN and NO3O2 are both total sample fractions, or when both are dissolved sample fractions. Future calculations of total nitrogen values may be based on components with mixed sample fractions.
  • Values inserted into data:
    • ParameterName = “Total Nitrogen”
    • SEACAR_QAQCFlagCode = “1Q”
    • SEACAR_QAQC_Description = “SEACAR Calculated”

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average total nitrogen over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only nitrogen values obtained from laboratory analyses (triangles) are included in the plot.
Scatter plot of monthly average total nitrogen over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only nitrogen values obtained from laboratory analyses (triangles) are included in the plot.
Seasonal Kendall-Tau Trend Analysis for Total Nitrogen
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Lab Significantly decreasing trend 34570 36 1989 - 2024 0.146 -0.2631 0.257 -0.0041 0

Monthly average total nitrogen decreased by less than 0.01 mg/L per year.

Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Total Nitrogen
ProgramID N_Data YearMin YearMax
297 26153 1995 2023
5002 4797 1998 2024
514 2907 1998 2024
509 1424 1989 2008
103 149 2000 2006
115 28 2000 2004

Program names:

103 - EPA STOrage and RETrieval Data Warehouse (STORET)/WQX5
115 - Environmental Monitoring Assessment Program6
297 - Florida Keys National Marine Sanctuary Water Quality Monitoring Project8
509 - SERC Water Quality Monitoring Network9
514 - Florida LAKEWATCH Program1
5002 - Florida STORET / WIN2

Total Phosphorus - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average total phosphorus over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only phosphorus values obtained from laboratory analyses (triangles) are included in the plot.
Scatter plot of monthly average total phosphorus over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only phosphorus values obtained from laboratory analyses (triangles) are included in the plot.
Seasonal Kendall-Tau Trend Analysis for Total Phosphorus
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Lab Significantly decreasing trend 32282 37 1970 - 2024 0.0059 -0.0865 0.0074 0 0.0125

Monthly average total phosphorus decreased by less than 0.01 mg/L per year.

Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Total Phosphorus
ProgramID N_Data YearMin YearMax
297 26170 1995 2023
514 2914 1998 2024
5002 2121 2005 2024
509 1425 1989 2008
103 182 1970 2021
115 28 2000 2004

Program names:

103 - EPA STOrage and RETrieval Data Warehouse (STORET)/WQX5
115 - Environmental Monitoring Assessment Program6
297 - Florida Keys National Marine Sanctuary Water Quality Monitoring Project8
509 - SERC Water Quality Monitoring Network9
514 - Florida LAKEWATCH Program1
5002 - Florida STORET / WIN2

Total Suspended Solids - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average total suspended solids (TSS) over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only TSS values obtained from laboratory analyses (triangles) are included in the plot.
Scatter plot of monthly average total suspended solids (TSS) over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only TSS values obtained from laboratory analyses (triangles) are included in the plot.
Seasonal Kendall-Tau Trend Analysis for Total Suspended Solids
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Lab Significantly decreasing trend 536 18 2007 - 2024 12 -0.5976 50.053 -4.7089 0

Monthly average total suspended solids decreased by 4.71 mg/L per year, indicating an increase in water clarity.

Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Total Suspended Solids
ProgramID N_Data YearMin YearMax
3 1391 2001 2012
5002 548 2007 2024
103 1 2020 2020

Program names:

3 - Atlantic Oceanographic and Meteorological Laboratory (AOML) South Florida Program Synoptic Shipboard Surveys3
103 - EPA STOrage and RETrieval Data Warehouse (STORET)/WQX5
5002 - Florida STORET / WIN2

Turbidity - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average turbidity over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only turbidity values measured in the laboratory (triangles) are included in the plot.
Scatter plot of monthly average turbidity over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only turbidity values measured in the laboratory (triangles) are included in the plot.
Seasonal Kendall-Tau Trend Analysis for Turbidity
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Lab No significant trend 3529 34 1991 - 2024 0.705 -0.0203 0.8692 -0.0015 0.5837

Turbidity showed no detectable trend between 1991 and 2024.

Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Turbidity
ProgramID N_Data YearMin YearMax
297 26741 1995 2023
5002 2144 1994 2024
509 1404 1991 2008
965 1157 2005 2011
3000 370 2015 2018
103 117 2005 2021

Program names:

103 - EPA STOrage and RETrieval Data Warehouse (STORET)/WQX5
297 - Florida Keys National Marine Sanctuary Water Quality Monitoring Project8
509 - SERC Water Quality Monitoring Network9
965 - South Florida Seagrass Fish and Invertebrate Assessment Network18
3000 - Florida Keys Water Watch14
5002 - Florida STORET / WIN2

Water Temperature - Discrete

Seasonal Kendall-Tau Trend Analysis

Scatter plot of monthly average water temperature over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only water temperature measurements taken in the field (circles) are included in the plot.
Scatter plot of monthly average water temperature over time. If the time series included ten or more years of discrete observations, a significant (blue) or non-significant (magenta) trend line is also shown. Only water temperature measurements taken in the field (circles) are included in the plot.
Seasonal Kendall-Tau Trend Analysis for Water Temperature
Activity Type Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Field Significantly increasing trend 53391 49 1955 - 2024 27.1769 0.2247 24.6007 0.0269 0

Monthly average water temperature increased by 0.03°C per year.

Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of discrete water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Programs contributing data for Water Temperature
ProgramID N_Data YearMin YearMax
297 31793 1995 2023
5002 5723 2003 2024
509 2601 1989 2008
965 2317 2005 2011
95 1957 1955 2018
3 1853 1998 2012
69 1776 1997 2022
60 1582 1993 2016
4049 1168 2005 2023
982 1129 2014 2023
103 875 1970 2021
3000 374 2015 2018
115 89 2000 2004
899 85 2014 2015
4057 59 2015 2018
102 43 1996 2000

Program names:

3 - Atlantic Oceanographic and Meteorological Laboratory (AOML) South Florida Program Synoptic Shipboard Surveys3
60 - Southeast Area Monitoring and Assessment Program (SEAMAP) - Gulf of Mexico Fall & Summer Shrimp/Groundfish Survey4
69 - Fisheries-Independent Monitoring (FIM) Program10
95 - Harmful Algal Bloom Marine Observation Network11
102 - National Status and Trends Mussel Watch12
103 - EPA STOrage and RETrieval Data Warehouse (STORET)/WQX5
115 - Environmental Monitoring Assessment Program6
297 - Florida Keys National Marine Sanctuary Water Quality Monitoring Project8
509 - SERC Water Quality Monitoring Network9
899 - USGS Coral Reef Ecosystem Studies (CREST) Project13
965 - South Florida Seagrass Fish and Invertebrate Assessment Network18
982 - Florida Keys Bleach Watch19
3000 - Florida Keys Water Watch14
4049 - The South Florida Fisheries Habitat Assessment Program (FHAP)15
4057 - Biscayne Bay Water Watch16
5002 - Florida STORET / WIN2

Water Quality - Continuous

The following files were used in the continuous analysis:

  • Combined_WQ_WC_NUT_cont_Dissolved_Oxygen_SE-2025-Mar-06.txt

  • Combined_WQ_WC_NUT_cont_Dissolved_Oxygen_Saturation_SE-2025-Mar-06.txt

  • Combined_WQ_WC_NUT_cont_pH_SE-2025-Mar-06.txt

  • Combined_WQ_WC_NUT_cont_Salinity_SE-2025-Mar-06.txt

  • Combined_WQ_WC_NUT_cont_Turbidity_SE-2025-Mar-06.txt

  • Combined_WQ_WC_NUT_cont_Water_Temperature_SE-2025-Mar-06.txt

Continuous monitoring locations in Florida Keys National Marine Sanctuary

Station overview for Continuous parameters by Program
ProgramID ProgramLocationID Years of Data Use in Analysis Parameters
2 1B 6 TRUE Sal , TempW
5 KYWF1 20 TRUE TempW
5 LONF1 28 TRUE TempW
5 MLRF1 33 TRUE TempW
5 SANF1 15 TRUE TempW
5 SMKF1 21 TRUE TempW
7 245323080410100 3 FALSE Sal , TempW
7 245622080364200 3 FALSE Sal , TempW
296 214 18 TRUE TempW
296 215 16 TRUE TempW
296 216 17 TRUE TempW
296 220 17 TRUE TempW
296 223 18 TRUE TempW
296 225 18 TRUE TempW
296 227 17 TRUE TempW
296 235 18 TRUE TempW
296 237 18 TRUE TempW
296 239 17 TRUE TempW
296 241 18 TRUE TempW
296 243 18 TRUE TempW
296 248 18 TRUE TempW
296 255 18 TRUE TempW
296 260 18 TRUE TempW
296 267 18 TRUE TempW
296 269 18 TRUE TempW
296 271 18 TRUE TempW
296 273 18 TRUE TempW
296 276 18 TRUE TempW
296 284 18 TRUE TempW
296 285 18 TRUE TempW
296 287 18 TRUE TempW
296 291 18 TRUE TempW
296 294 18 TRUE TempW
296 296 18 TRUE TempW
296 305 18 TRUE TempW
296 307 18 TRUE TempW
296 309 18 TRUE TempW
296 314 18 TRUE TempW
296 500 8 TRUE TempW
296 501 7 TRUE TempW
296 502 4 FALSE TempW
296 503 1 FALSE TempW
296 504 1 FALSE TempW
296 506 8 TRUE TempW
296 507 8 TRUE TempW
296 508 8 TRUE TempW
296 509 8 TRUE TempW
296 SB 19 TRUE TempW
899 Crocker 10 TRUE TempW
899 Molasses 5 TRUE TempW
899 Sombrero 14 TRUE TempW
986 10 3 FALSE TempW
986 11 20 TRUE TempW
986 12 15 TRUE TempW
986 14 21 TRUE TempW
986 15 17 TRUE TempW
986 18 7 TRUE TempW
986 21 7 TRUE TempW
986 22 14 TRUE TempW
986 23 11 TRUE TempW
986 24 13 TRUE TempW
986 25 13 TRUE TempW
986 26 14 TRUE TempW
986 30 11 TRUE TempW
986 32 20 TRUE TempW
986 33 7 TRUE TempW
986 34 21 TRUE TempW
986 35 17 TRUE TempW
986 36 16 TRUE TempW
986 37 7 TRUE TempW
986 38 21 TRUE TempW
986 39 5 TRUE TempW
986 40 21 TRUE TempW
986 50 10 TRUE TempW
986 51 20 TRUE TempW
986 52 15 TRUE TempW
986 53 15 TRUE TempW
986 54 11 TRUE TempW
986 55 21 TRUE TempW
986 56 17 TRUE TempW
986 57 15 TRUE TempW
986 58 9 TRUE TempW
986 59 21 TRUE TempW
986 60 14 TRUE TempW
986 61 7 TRUE TempW
986 70 10 TRUE TempW
986 72 15 TRUE TempW
986 73 15 TRUE TempW
986 74 11 TRUE TempW
986 75 13 TRUE TempW
986 76 14 TRUE TempW
986 77 15 TRUE TempW
986 78 9 TRUE TempW
986 79 16 TRUE TempW
986 80 14 TRUE TempW
986 81 7 TRUE TempW
986 83 17 TRUE TempW
989 FKNMS_200YR_HD 12 TRUE TempW
989 FKNMS_7MILE_BR 20 TRUE TempW
989 FKNMS_9FT_SHOAL 21 TRUE TempW
989 FKNMS_ALLIGATOR 21 TRUE TempW
989 FKNMS_BHONDA_BR 22 TRUE TempW
989 FKNMS_BOCA_GRND 23 TRUE TempW
989 FKNMS_BULLARD 18 TRUE TempW
989 FKNMS_CARD_SND 6 TRUE TempW
989 FKNMS_CARYSFORT 17 TRUE TempW
989 FKNMS_DIEGO_TER 5 TRUE TempW
989 FKNMS_ELPIS 8 TRUE TempW
989 FKNMS_GRECIAN 21 TRUE TempW
989 FKNMS_HARBORKEY 6 TRUE TempW
989 FKNMS_HEN&CHIX 23 TRUE TempW
989 FKNMS_KW_CHANL 22 TRUE TempW
989 FKNMS_LONG_KEY 21 TRUE TempW
989 FKNMS_LOOE_BACK 23 TRUE TempW
989 FKNMS_LOOE_BUOY5 11 TRUE TempW
989 FKNMS_LOOE_ISELIN 16 TRUE TempW
989 FKNMS_MAITLAND 4 FALSE TempW
989 FKNMS_MOLASSES 13 TRUE TempW
989 FKNMS_NEWGROUND 15 TRUE TempW
989 FKNMS_PILLAR 11 TRUE TempW
989 FKNMS_SAND_KEY 21 TRUE TempW
989 FKNMS_SMITH_SHL 15 TRUE TempW
989 FKNMS_SNAKE_CRK 19 TRUE TempW
989 FKNMS_SOMBRERO 15 TRUE TempW
989 FKNMS_SPRIGGER 15 TRUE TempW
989 FKNMS_TENN_REEF 17 TRUE TempW
989 FKNMS_WELLWOOD 8 TRUE TempW
989 FKNMS_WS_BUOY16 3 FALSE TempW
989 FKNMS_WS_JACKYL 9 TRUE TempW
989 FKNMS_W_SAMBO 6 TRUE TempW
10004 FKCB 1 FALSE DO , DOS , pH , Sal , Turb , TempW
10004 FKLK 1 FALSE DO , DOS , pH , Sal , Turb , TempW

Program names:

2 - Atlantic Oceanographic and Meteorological Laboratory (AOML) South Florida Program Moored Instrument Array20
5 - National Data Buoy Center21
7 - National Water Information System22
296 - Florida Keys National Marine Sanctuary Seagrass Monitoring Project23
899 - USGS Coral Reef Ecosystem Studies (CREST) Project13
986 - Water Temperature on Coral Reefs in the Florida Keys24
989 - Continuous Bottom Temperature Measurements along the Florida Reef Tract25
10004 - Florida Keys Aquatic Preserves Continuous Water Quality Monitoring26

Map showing continuous water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. Sites marked as Use In Analysis (green) are featured in this report.
Map showing continuous water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. Sites marked as Use In Analysis (green) are featured in this report.

Dissolved Oxygen - Continuous

Scatter plot of monthly average dissolved oxygen over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Scatter plot of monthly average dissolved oxygen over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Seasonal Kendall-Tau Results for Dissolved Oxygen - All Stations
Station Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
FKLK Insufficient data to calculate trend 21525 1 2024 - 2024 6.2 - - - -
FKCB Insufficient data to calculate trend 16262 1 2024 - 2024 6.8 - - - -

There was insufficient data to fit a model for two locations.

Map showing location of dissolved oxygen continuous water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of dissolved oxygen continuous water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.

Dissolved Oxygen Saturation - Continuous

Scatter plot of monthly average dissolved oxygen saturation over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Scatter plot of monthly average dissolved oxygen saturation over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Seasonal Kendall-Tau Results for Dissolved Oxygen Saturation - All Stations
Station Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
FKLK Insufficient data to calculate trend 21525 1 2024 - 2024 91.9 - - - -
FKCB Insufficient data to calculate trend 16263 1 2024 - 2024 103.3 - - - -

There was insufficient data to fit a model for two locations.

Map showing location of dissolved oxygen saturation continuous water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of dissolved oxygen saturation continuous water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.

pH - Continuous

Scatter plot of monthly average pH over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Scatter plot of monthly average pH over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Seasonal Kendall-Tau Results for pH - All Stations
Station Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
FKLK Insufficient data to calculate trend 21517 1 2024 - 2024 8.1 - - - -
FKCB Insufficient data to calculate trend 16263 1 2024 - 2024 8.2 - - - -

There was insufficient data to fit a model for two locations.

Map showing location of ph continuous water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of ph continuous water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.

Salinity - Continuous

Scatter plot of monthly average salinity over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Scatter plot of monthly average salinity over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Seasonal Kendall-Tau Results for Salinity - All Stations
Station Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
1B No significant trend 86204 6 2003 - 2008 36.07 0.24 35.68 0.17 0.05
245323080410100 Insufficient data to calculate trend 746 3 2002 - 2004 35.00 - - - -
245622080364200 Insufficient data to calculate trend 764 3 2002 - 2004 35.00 - - - -
FKLK Insufficient data to calculate trend 21517 1 2024 - 2024 36.10 - - - -
FKCB Insufficient data to calculate trend 16258 1 2024 - 2024 36.50 - - - -

No detectable change in monthly average salinity was observed at one location. There was insufficient data to fit a model for four locations.

Map showing location of salinity continuous water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of salinity continuous water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.

Turbidity - Continuous

Scatter plot of monthly average turbidity over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Scatter plot of monthly average turbidity over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Seasonal Kendall-Tau Results for Turbidity - All Stations
Station Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
FKLK Insufficient data to calculate trend 21399 1 2024 - 2024 6 - - - -
FKCB Insufficient data to calculate trend 16240 1 2024 - 2024 4 - - - -

There was insufficient data to fit a model for two locations.

Map showing location of turbidity continuous water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of turbidity continuous water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.

Water Temperature - Continuous - Program 2

Scatter plot of monthly average water temperature over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Scatter plot of monthly average water temperature over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Seasonal Kendall-Tau Results for Water Temperature - Program 2
Station Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
1B Significantly increasing trend 86204 6 2003 - 2008 26.38 0.26 25.73 0.16 0.04

At seventy-four program locations, monthly average water temperature increased between 0.01 and 0.16°C per year. No detectable change in monthly average water temperature was observed at forty-eight locations. There was insufficient data to fit a model for ten locations.

Water Temperature - Continuous - Program 5

Scatter plot of monthly average water temperature over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Scatter plot of monthly average water temperature over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Seasonal Kendall-Tau Results for Water Temperature - Program 5
Station Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
SMKF1 Significantly increasing trend 154326 21 1988 - 2008 26.8 0.34 26.24 0.06 0.00
KYWF1 Significantly increasing trend 1441302 20 2005 - 2024 27.6 0.31 26.65 0.07 0.00
LONF1 No significant trend 205971 28 1992 - 2019 26.6 0.07 26.34 0.01 0.08
MLRF1 Significantly increasing trend 256798 33 1987 - 2019 26.5 0.10 26.49 0.01 0.00
SANF1 No significant trend 117833 15 1991 - 2005 26.7 -0.03 26.69 0.00 0.62

At seventy-four program locations, monthly average water temperature increased between 0.01 and 0.16°C per year. No detectable change in monthly average water temperature was observed at forty-eight locations. There was insufficient data to fit a model for ten locations.

Water Temperature - Continuous - Program 7

Scatter plot of monthly average water temperature over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Scatter plot of monthly average water temperature over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Seasonal Kendall-Tau Results for Water Temperature - Program 7
Station Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
245323080410100 Insufficient data to calculate trend 791 3 2002 - 2004 27.9 - - - -
245622080364200 Insufficient data to calculate trend 853 3 2002 - 2004 28.3 - - - -

At seventy-four program locations, monthly average water temperature increased between 0.01 and 0.16°C per year. No detectable change in monthly average water temperature was observed at forty-eight locations. There was insufficient data to fit a model for ten locations.

Water Temperature - Continuous - Program 296

Scatter plot of monthly average water temperature over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Scatter plot of monthly average water temperature over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Seasonal Kendall-Tau Results for Water Temperature - Program 296
Station Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
241 Significantly increasing trend 127914 18 2002 - 2019 27.26 0.27 25.91 0.09 0
243 Significantly increasing trend 121593 18 2002 - 2019 26.62 0.3 26 0.07 0
255 Significantly increasing trend 119939 18 2002 - 2019 26.35 0.24 25.73 0.07 0
260 Significantly increasing trend 97832 16 2002 - 2019 27.07 0.28 26.22 0.08 0
284 Significantly increasing trend 123977 17 2002 - 2019 26.86 0.28 25.14 0.09 0
285 Significantly increasing trend 121423 18 2002 - 2019 26.86 0.25 26.17 0.07 0
287 Significantly increasing trend 133008 18 2002 - 2019 26.87 0.29 25.84 0.08 0
291 Significantly increasing trend 116240 18 2002 - 2019 26.38 0.26 25.72 0.09 0
294 Significantly increasing trend 112348 18 2002 - 2019 26.92 0.27 25.52 0.09 0
239 Significantly increasing trend 111523 17 2002 - 2018 26.92 0.24 25.96 0.07 0
267 Significantly increasing trend 99735 18 2002 - 2019 26.57 0.24 25.64 0.05 0
269 Significantly increasing trend 106458 17 2002 - 2019 26.74 0.21 26.02 0.05 0
271 Significantly increasing trend 133627 18 2002 - 2019 26.92 0.26 25.77 0.07 0
273 Significantly increasing trend 129817 18 2002 - 2019 27.16 0.24 26.16 0.05 0
276 Significantly increasing trend 123833 18 2002 - 2019 26.87 0.21 26.15 0.05 0
216 Significantly increasing trend 98535 17 2002 - 2018 26.26 0.31 25.86 0.06 0
220 Significantly increasing trend 126033 17 2003 - 2019 26.52 0.25 25.94 0.06 0
223 Significantly increasing trend 133082 18 2002 - 2019 26.89 0.3 25.84 0.08 0
225 Significantly increasing trend 117692 17 2002 - 2019 26.82 0.32 26.32 0.06 0
227 Significantly increasing trend 105351 17 2003 - 2019 26.67 0.29 26.06 0.08 0
235 Significantly increasing trend 128499 18 2002 - 2019 27.14 0.28 25.77 0.08 0
237 Significantly increasing trend 122250 18 2002 - 2019 26.38 0.31 25.74 0.09 0
296 Significantly increasing trend 114497 17 2002 - 2019 27.36 0.21 25.45 0.07 0
305 Significantly increasing trend 122296 18 2002 - 2019 26.43 0.22 26.07 0.06 0
307 Significantly increasing trend 110802 17 2002 - 2019 26.74 0.22 25.73 0.07 0
SB Significantly increasing trend 145514 19 2001 - 2019 26.34 0.23 25.9 0.06 0
214 Significantly increasing trend 136333 18 2002 - 2019 26.52 0.27 25.84 0.07 0
215 Significantly increasing trend 133286 16 2003 - 2018 26.74 0.26 26.42 0.05 0
314 Significantly increasing trend 110686 18 2002 - 2019 27.41 0.23 25.63 0.06 0
309 Significantly increasing trend 107410 18 2002 - 2019 27.85 0.27 26.07 0.06 0
248 Significantly increasing trend 111702 18 2002 - 2019 26.79 0.31 25.54 0.08 0
500 Significantly increasing trend 69048 8 2012 - 2019 27.33 0.23 26.79 0.12 0.01
506 No significant trend 35198 7 2012 - 2019 27.41 0.04 27.2 0.05 0.74
507 No significant trend 47517 8 2012 - 2019 27.36 0.18 27.48 0.09 0.12
508 No significant trend 24021 6 2012 - 2019 26.67 0.33 26.54 0.07 0.29
509 No significant trend 38607 8 2012 - 2019 27.70 0.05 27.79 0.11 0.47
502 Insufficient data to calculate trend 22765 4 2016 - 2019 26.70 - - - -
501 No significant trend 34805 5 2012 - 2018 27.48 0.11 27.55 0.05 0.65
503 Insufficient data to calculate trend 7490 1 2016 - 2016 28.74 - - - -
504 Insufficient data to calculate trend 4339 1 2018 - 2018 29.84 - - - -

At seventy-four program locations, monthly average water temperature increased between 0.01 and 0.16°C per year. No detectable change in monthly average water temperature was observed at forty-eight locations. There was insufficient data to fit a model for ten locations.

Water Temperature - Continuous - Program 899

Scatter plot of monthly average water temperature over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Scatter plot of monthly average water temperature over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Seasonal Kendall-Tau Results for Water Temperature - Program 899
Station Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
Sombrero Significantly increasing trend 459354 14 2009 - 2022 27.16 0.26 26.83 0.05 0.00
Crocker Significantly increasing trend 322670 10 2013 - 2022 27.32 0.15 27.07 0.03 0.04
Molasses No significant trend 140713 5 2009 - 2013 26.72 -0.03 26.61 -0.04 0.92

At seventy-four program locations, monthly average water temperature increased between 0.01 and 0.16°C per year. No detectable change in monthly average water temperature was observed at forty-eight locations. There was insufficient data to fit a model for ten locations.

Water Temperature - Continuous - Program 986

Scatter plot of monthly average water temperature over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Scatter plot of monthly average water temperature over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Seasonal Kendall-Tau Results for Water Temperature - Program 986
Station Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
35 Significantly increasing trend 217666 17 2006 - 2022 26.84 0.22 26.41 0.05 0
36 Significantly increasing trend 192871 16 2007 - 2022 26.89 0.24 26.52 0.06 0
34 Significantly increasing trend 274006 21 2002 - 2022 26.74 0.31 26.19 0.07 0
56 Significantly increasing trend 175648 17 2006 - 2022 26.67 0.14 26.67 0.03 0.02
79 Significantly increasing trend 175394 16 2007 - 2022 26.79 0.21 26.56 0.04 0
53 Significantly increasing trend 179447 15 2008 - 2022 26.98 0.37 26.53 0.07 0
14 Significantly increasing trend 223851 19 2002 - 2022 26.84 0.24 26.31 0.06 0
24 Significantly increasing trend 111388 11 2010 - 2022 26.89 0.33 26.12 0.09 0
32 Significantly increasing trend 223104 18 2003 - 2022 26.69 0.31 26.09 0.06 0
40 Significantly increasing trend 244138 21 2002 - 2022 26.79 0.28 26.27 0.07 0
59 Significantly increasing trend 191677 18 2002 - 2022 26.81 0.27 26.85 0.05 0
22 Significantly increasing trend 171553 14 2009 - 2022 26.91 0.25 26.43 0.07 0
72 Significantly increasing trend 188119 15 2008 - 2022 26.77 0.42 26.42 0.08 0
15 Significantly increasing trend 212659 17 2006 - 2022 26.99 0.19 26.4 0.05 0
77 Significantly increasing trend 188336 15 2008 - 2022 26.89 0.27 26.57 0.07 0
76 Significantly increasing trend 168914 14 2009 - 2022 26.84 0.23 26.82 0.05 0
12 Significantly increasing trend 138064 13 2008 - 2022 27.16 0.21 26.39 0.06 0
57 Significantly increasing trend 187914 15 2008 - 2022 26.96 0.3 26.66 0.07 0
80 Significantly increasing trend 167362 14 2009 - 2022 26.87 0.21 26.92 0.05 0
74 Significantly increasing trend 130333 11 2012 - 2022 26.87 0.24 26.64 0.05 0
73 Significantly increasing trend 179435 15 2008 - 2022 26.74 0.35 26.49 0.07 0
58 No significant trend 72230 9 2014 - 2022 27.11 0.01 27.23 0.01 0.96
11 Significantly increasing trend 228643 18 2003 - 2022 26.81 0.3 26.1 0.06 0
55 Significantly increasing trend 225636 21 2002 - 2022 26.86 0.28 26.79 0.05 0
54 Significantly increasing trend 130399 11 2012 - 2022 27.06 0.25 26.77 0.06 0
75 Significantly increasing trend 144589 13 2010 - 2022 27.06 0.27 26.71 0.07 0
60 Significantly increasing trend 150013 14 2009 - 2022 26.94 0.17 27.07 0.04 0.01
38 Significantly increasing trend 256177 21 2002 - 2022 26.47 0.28 26.15 0.06 0
61 No significant trend 54044 7 2016 - 2022 27.06 0.15 26.58 0.05 0.15
33 No significant trend 38112 6 2016 - 2022 27.13 0.08 26.23 0.01 0.66
23 Significantly increasing trend 113161 11 2012 - 2022 27.33 0.19 26.83 0.07 0.01
83 Significantly increasing trend 130599 16 2006 - 2022 25.79 0.14 25.79 0.04 0.01
52 Significantly increasing trend 188237 15 2008 - 2022 26.92 0.34 26.63 0.07 0
39 No significant trend 33723 5 2018 - 2022 27.01 -0.09 27.6 -0.08 0.69
37 No significant trend 52521 7 2016 - 2022 26.74 0.07 26.3 0.05 0.47
78 No significant trend 87924 9 2014 - 2022 26.98 0.11 26.81 0.03 0.19
50 Significantly increasing trend 103998 10 2013 - 2022 27.01 0.23 26.85 0.05 0
18 No significant trend 44119 7 2016 - 2022 27.03 0.13 26.59 0.06 0.29
25 No significant trend 117274 12 2010 - 2022 27.19 0.08 27.07 0.03 0.27
26 Significantly increasing trend 142040 14 2009 - 2022 26.96 0.21 26.97 0.06 0
51 Significantly increasing trend 222780 18 2003 - 2022 26.67 0.31 26.27 0.06 0
30 Significantly increasing trend 116701 11 2012 - 2022 26.62 0.21 26.3 0.05 0.01
21 No significant trend 55870 7 2016 - 2022 27.18 0.13 26.51 0.04 0.22
81 No significant trend 53957 7 2016 - 2022 27.03 0.13 26.63 0.05 0.22
70 Significantly increasing trend 104819 10 2013 - 2022 26.91 0.22 26.73 0.05 0
10 Insufficient data to calculate trend 18268 3 2020 - 2022 27.72 - - - -

At seventy-four program locations, monthly average water temperature increased between 0.01 and 0.16°C per year. No detectable change in monthly average water temperature was observed at forty-eight locations. There was insufficient data to fit a model for ten locations.

Water Temperature - Continuous - Program 989

Scatter plot of monthly average water temperature over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Scatter plot of monthly average water temperature over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Seasonal Kendall-Tau Results for Water Temperature - Program 989
Station Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
FKNMS-SMITH-SHL No significant trend 94527 10 1998 - 2012 25.45 0.13 25.99 0.02 0.19
FKNMS-SAND-KEY No significant trend 59287 18 1990 - 2010 26.70 0.05 26.46 0.01 0.32
FKNMS-SPRIGGER No significant trend 41834 13 1992 - 2006 26.10 0.02 25.78 0 0.86
FKNMS-TENN-REEF No significant trend 63260 16 1990 - 2006 26.70 -0.06 26.22 -0.01 0.27
FKNMS-SOMBRERO No significant trend 48974 13 1991 - 2005 26.50 0.13 26.14 0.03 0.05
FKNMS-200YR-HD No significant trend 44601 12 1998 - 2009 26.10 -0.1 26.45 -0.04 0.17
FKNMS-7MILE-BR No significant trend 73055 19 1991 - 2010 26.66 0.05 26.22 0.01 0.35
FKNMS-DIEGO-TER No significant trend 16693 5 2002 - 2006 25.58 -0.05 25.91 -0.03 0.84
FKNMS-ELPIS No significant trend 31035 8 2004 - 2011 26.35 0.06 25.9 0.04 0.53
FKNMS-BHONDA-BR No significant trend 77111 22 1990 - 2011 26.60 -0.02 26.67 0 0.66
FKNMS-BULLARD Significantly increasing trend 66230 18 1992 - 2009 26.31 0.12 26.11 0.02 0.03
FKNMS-LOOE-ISELIN No significant trend 194367 13 1999 - 2014 26.88 0.13 26.55 0.03 0.08
FKNMS-PILLAR No significant trend 40805 11 1996 - 2006 26.24 0.02 26.04 0.01 0.94
FKNMS-MOLASSES No significant trend 36146 13 1990 - 2002 26.70 -0.05 26.74 -0.01 0.48
FKNMS-BOCA-GRND No significant trend 73434 17 1990 - 2012 26.14 0.08 26.04 0.01 0.17
FKNMS-MAITLAND Insufficient data to calculate trend 12421 4 2004 - 2007 26.07 - - - -
FKNMS-CARYSFORT No significant trend 55001 16 1990 - 2006 26.40 -0.03 26.38 0 0.64
FKNMS-9FT-SHOAL No significant trend 80299 21 1990 - 2010 26.50 0 26.76 0 0.99
FKNMS-HEN-and-CHIX No significant trend 72285 21 1989 - 2011 26.50 -0.01 26.35 0 0.88
FKNMS-KW-CHANL No significant trend 123578 18 1991 - 2012 26.27 0.1 26.11 0.02 0.08
FKNMS-GRECIAN No significant trend 51723 18 1990 - 2010 26.65 -0.03 26.48 0 0.66
FKNMS-LONG-KEY No significant trend 69656 19 1990 - 2010 26.64 -0.03 26.35 -0.01 0.58
FKNMS-WELLWOOD No significant trend 30427 8 2002 - 2009 26.43 0 26.82 0 1
FKNMS-SNAKE-CRK No significant trend 56777 19 1989 - 2007 26.16 -0.06 26.33 -0.02 0.28
FKNMS-ALLIGATOR No significant trend 65144 19 1990 - 2010 26.55 -0.06 26.72 -0.01 0.23
FKNMS-W-SAMBO No significant trend 18786 6 1990 - 1995 26.90 0.09 26.16 0.03 0.56
FKNMS-LOOE-BACK No significant trend 84984 18 1990 - 2012 26.80 -0.06 26.6 -0.01 0.42
FKNMS-LOOE-BUOY5 No significant trend 35252 10 1988 - 1998 26.90 0.05 26.86 0.02 0.36
FKNMS-NEWGROUND No significant trend 35329 12 1992 - 2006 25.49 -0.05 25.73 -0.01 0.52
FKNMS-WS-JACKYL No significant trend 29557 9 1991 - 1999 26.40 0.17 26.96 0.06 0.09
FKNMS-CARD-SND No significant trend 18249 6 2001 - 2006 26.52 -0.05 27.32 -0.05 0.79
FKNMS-HARBORKEY No significant trend 15407 5 1992 - 1997 26.50 0.14 25.74 0.14 0.33
FKNMS-WS-BUOY16 Insufficient data to calculate trend 8123 3 2003 - 2005 25.99 - - - -

At seventy-four program locations, monthly average water temperature increased between 0.01 and 0.16°C per year. No detectable change in monthly average water temperature was observed at forty-eight locations. There was insufficient data to fit a model for ten locations.

Water Temperature - Continuous - Program 10004

Scatter plot of monthly average water temperature over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Scatter plot of monthly average water temperature over time at continuously monitored program locations. Each location is analyzed separately, with significant (blue) or non-significant (magenta) trend lines shown for time series that included five or more years of observations.
Seasonal Kendall-Tau Results for Water Temperature - Program 10004
Station Statistical Trend Sample Count Years with Data Period of Record Median tau Sen Intercept Sen Slope p
FKLK Insufficient data to calculate trend 21517 1 2024 - 2024 29.0 - - - -
FKCB Insufficient data to calculate trend 16263 1 2024 - 2024 26.8 - - - -

At seventy-four program locations, monthly average water temperature increased between 0.01 and 0.16°C per year. No detectable change in monthly average water temperature was observed at forty-eight locations. There was insufficient data to fit a model for ten locations.

Map showing location of water temperature continuous water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of water temperature continuous water quality sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.

Submerged Aquatic Vegetation

The data file used is: All_SAV_Parameters-2025-Mar-06.txt

Submerged aquatic vegetation (SAV) refers to plants and plant-like macroalgae species that live entirely underwater. The two primary categories of SAV inhabiting Florida estuaries are benthic macroalgae and seagrasses. They often grow together in dense beds or meadows that carpet the seafloor. Macroalgae include multicellular species of green, red and brown algae that often live attached to the substrate by a holdfast. They tend to grow quickly and can tolerate relatively high nutrient levels, making them a threat to seagrasses and other benthic habitats in areas with poor water quality. In contrast, seagrasses are grass-like, vascular, flowering plants that are attached to the seafloor by extensive root systems. Seagrasses occur throughout the coastal areas of Florida, including protected bays and lagoons as well as deeper offshore waters on the continental shelf. Seagrasses have taken advantage of the broad, shallow shelf and clear water to produce two of the most extensive seagrass beds anywhere in continental North America.

Parameters

Percent Cover measures the fraction of an area of seafloor that is covered by SAV, usually estimated by evaluating multiple small areas of seafloor. Percent cover is often estimated for total SAV, individual types of vegetation (seagrass, attached algae, drift algae) and individual species.

Frequency of Occurrence was calculated as the number of times a taxon was observed in a year divided by the number of sampling events, multiplied by 100. Analysis is conducted at the quadrat level and is inclusive of all quadrats (i.e., quadrats evaluated using Braun-Blanquet, modified Braun-Blanquet, and percent cover.”

Species

Turtle grass (Thalassia testudinum) is the largest of the Florida seagrasses, with longer, thicker blades and deeper root structures than any of the other seagrasses. It is considered a climax seagrass species.

Shoal grass (Halodule wrightii) is an early colonizer of vegetated areas and usually grows in water too shallow for other species except widgeon grass. It can often tolerate larger salinity ranges than other seagrass species. Shoal grass is characterized by thin, flat blades, that are narrower than turtle grass blades.

Manatee grass (Syringodium filiforme) is easily recognizable because its leaves are thin and cylindrical instead of the flat, ribbon-like form shared by many other seagrass species. The leaves can grow up to half a meter in length. Manatee grass is usually found in mixed seagrass beds or small, dense monospecific patches.

Widgeon grass (Ruppia maritima) grows in both fresh and salt water and is widely distributed throughout Florida’s estuaries in less saline areas, particularly in inlets along the east coast. This species resembles shoal grass in certain environments but can be identified by the pointed tips of its leaves.

Three species of Halophila spp. are found in Florida - Star grass (Halophila engelmannii), Paddle grass (Halophila decipiens), and Johnson’s seagrass (Halophila johnsonii). These are smaller, more fragile seagrasses than other Florida species and are considered ephemeral. They grow along a single long rhizome, with short blades. These species are not well-studied, although surveys are underway to define their ecological roles.

Notes

Star grass, Paddle grass, and Johnson’s seagrass will be grouped together and listed as Halophila spp. in the following managed areas. This is because several surveys did not specify to the species level:

  • Banana River Aquatic Preserve

  • Indian River-Malabar to Vero Beach Aquatic Preserve

  • Indian River-Vero Beach to Ft. Pierce Aquatic Preserve

  • Jensen Beach to Jupiter Inlet Aquatic Preserve

  • Loxahatchee River-Lake Worth Creek Aquatic Preserve

  • Mosquito Lagoon Aquatic Preserve

  • Biscayne Bay Aquatic Preserve

  • Florida Keys National Marine Sanctuary

Maps showing the temporal scope of SAV sampling sites within the boundaries of Florida Keys National Marine Sanctuary by Program name.
Maps showing the temporal scope of SAV sampling sites within the boundaries of Florida Keys National Marine Sanctuary by Program name.

Click here to view spatio-temporal plots on GitHub.

Sampling locations by Program:

Map showing SAV sampling sites within the boundaries of Florida Keys National Marine Sanctuary. The point size reflects the number of samples at a given sampling site.
Map showing SAV sampling sites within the boundaries of Florida Keys National Marine Sanctuary. The point size reflects the number of samples at a given sampling site.
Program Information for Submerged Aquatic Vegetation
ProgramID N-Data YearMin YearMax method Sample Locations
296 4200 1996 2021 Braun Blanquet 40
965 65538 2005 2011 Braun Blanquet 87
4018 3925 1999 2023 Braun Blanquet 115
4049 104563 2005 2024 Braun Blanquet 1267
4018 279 1999 2007 Percent Cover 67

Program names:

296 - Florida Keys National Marine Sanctuary Seagrass Monitoring Project23
965 - South Florida Seagrass Fish and Invertebrate Assessment Network18
4018 - Miami-Dade County DERM Benthic Habitat Monitoring Program27
4018 - Miami-Dade County DERM Benthic Habitat Monitoring Program27
4049 - The South Florida Fisheries Habitat Assessment Program (FHAP)15

Scatter plots of median percent cover of submerged aquatic vegetation over time by group. Plots for time series that included five or more years of observations show the estimated trend as a blue line.
Scatter plots of median percent cover of submerged aquatic vegetation over time by group. Plots for time series that included five or more years of observations show the estimated trend as a blue line.
Trends in median percent cover for various seagrass species in Florida Keys National Marine Sanctuary - simplified
Trends in median percent cover for various seagrass species in Florida Keys National Marine Sanctuary - simplified
Percent Cover Trend Analysis for Florida Keys National Marine Sanctuary
CommonName Trend Significance (0.05) Period of Record LME-Intercept LME-Slope p
Attached algae No significant trend 2008 - 2024 0.0761161 -0.0025432 0.2165299
Drift algae Significantly decreasing trend 1999 - 2024 9.1453632 -0.2334903 0.0000182
Shoal grass Significantly decreasing trend 1996 - 2024 7.0786462 -0.2741281 0.0001016
Halophila spp. No significant trend 2005 - 2024 0.0749728 -0.0023143 0.3291618
Widgeon grass No significant trend 2005 - 2024 -0.0383108 0.0028175 0.1044281
Manatee grass Significantly decreasing trend 1996 - 2024 4.9248479 -0.1110174 0.0174460
Turtle grass Significantly decreasing trend 1996 - 2024 43.8162349 -1.4638927 0.0000000
Total SAV No significant trend 1999 - 2024 31.5258442 0.2203815 0.1700662
Total seagrass Significantly increasing trend 2005 - 2024 16.4149550 0.2503526 0.0067937

An annual increase in percent cover was observed for total seagrass (0.2%). Annual decreases in percent cover were observed for manatee grass (-0.1%), shoal grass (-0.3%), turtle grass (-1.5%), and drift algae (-0.2%). Total SAV, Halophila spp., widgeon grass, and attached algae showed no detectable change in percent cover.

Frequency of occurrence for various seagrass species in Florida Keys National Marine Sanctuary
Frequency of occurrence for various seagrass species in Florida Keys National Marine Sanctuary

Coral Reef

The data file used is: All_CORAL_Parameters-2025-Mar-06.txt

Percent Cover

Scatter plot of live coral coverage over time as a percent of reef surface. Species groups include octocorals, milleporans, and scleractinians. If the time series included five or more years of observations, a significant (blue) or non-significant (magenta) trend line is also shown. Data points are jittered horizontally to reduce overlap.
Scatter plot of live coral coverage over time as a percent of reef surface. Species groups include octocorals, milleporans, and scleractinians. If the time series included five or more years of observations, a significant (blue) or non-significant (magenta) trend line is also shown. Data points are jittered horizontally to reduce overlap.
Coral Percent Cover
Statistical Trend Period of Record LME Intercept LME Slope p
No significant trend 1996 - 2021 4.96407 -0.00233 0.05266

Percent cover showed no detectable trend between 1996 and 2021.

Map showing location of coral percent cover sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of coral percent cover sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.

Species Richness

Line graph of annual average species richness of grazers and reef-dependent species over time. If the time series included more than one year of observations, a line connects the data points for visualization.
Line graph of annual average species richness of grazers and reef-dependent species over time. If the time series included more than one year of observations, a line connects the data points for visualization.
Coral Species Richness
Sample Count Number of Years Period of Record Median N of Taxa Mean N of Taxa
11167 21 1999 - 2019 281 220.2253

The median annual number of taxa was 281 based on 11,167 observations collected between 1999 and 2019.

Map showing location of coral species richness sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.
Map showing location of coral species richness sampling locations within the boundaries of Florida Keys National Marine Sanctuary. The bubble size on the maps above reflect the amount of data available at each sampling site.

References

1.
University of Florida (UF); Institute of Food and Agricultural Sciences. Florida LAKEWATCH Program. (2024).
2.
Florida Department of Environmental Protection (DEP). Florida STORET / WIN. (2024).
3.
National Oceanic and Atmospheric Administration (NOAA); Atlantic Oceanographic and Meterological Laboratory. Atlantic Oceanographic and Meteorological Laboratory (AOML) South Florida Program Synoptic Shipboard Surveys. (2024).
4.
Gulf States Marine Fisheries Commission. Southeast Area Monitoring and Assessment Program (SEAMAP) - Gulf of Mexico Fall & Summer Shrimp/Groundfish Survey. (2016).
5.
U.S. Environmental Protection Agency (EPA). EPA STOrage and RETrieval Data Warehouse (STORET)/WQX. (2023).
6.
U.S. Environmental Protection Agency (EPA); Office of Research and Development. Environmental Monitoring Assessment Program. (2004).
7.
U.S. Environmental Protection Agency (EPA); Office of Water; National Oceanic and Atmospheric Administration (NOAA); U.S. Geological Survey (USGS); U.S. Fish and Wildlife Service (USFWS); National Estuary Program (NEP); coastal states. National Aquatic Resource Surveys, National Coastal Condition Assessment. (2021).
8.
Florida International University (FIU). Florida Keys National Marine Sanctuary Water Quality Monitoring Project. (2023).
9.
Florida International University (FIU); Southeastern Environmental Research Program. SERC Water Quality Monitoring Network. (2008).
10.
Florida Fish and Wildlife Conservation Commission (FWC). Fisheries-Independent Monitoring (FIM) Program. (2022).
11.
Florida Fish and Wildlife Conservation Commission (FWC); Florida Fish and Wildlife Research Institute (FWRI). Harmful Algal Bloom Marine Observation Network. (2018).
12.
National Oceanic and Atmospheric Administration (NOAA); Center for Coastal Monitoring and Assessment. National Status and Trends Mussel Watch. (2000).
13.
U.S. Geological Survey (USGS); St. Petersburg Coastal and Marine Science Center. USGS Coral Reef Ecosystem Studies (CREST) Project. (2022).
14.
Florida Sea Grant; University of Florida IFAS Extension; Monroe County. Florida Keys Water Watch. (2019).
15.
Florida Fish and Wildlife Conservation Commission (FWC); Florida Fish and Wildlife Research Institute (FWRI). The South Florida Fisheries Habitat Assessment Program (FHAP). (2024).
16.
University of Florida; Florida Sea Grant; UF/IFAS Extension Miami-Dade County; Miami Waterkeeper . Biscayne Bay Water Watch . (2019).
17.
Gulf States Marine Fisheries Commission. Southeast Area Monitoring and Assessment Program (SEAMAP) - Gulf of Mexico Reef Fish Survey. (2021).
18.
U.S. Geological Survey (USGS). South Florida Seagrass Fish and Invertebrate Assessment Network. (2011).
19.
Mote Marine Laboratory. Florida Keys Bleach Watch. (2023).
20.
National Oceanic and Atmospheric Administration (NOAA); Atlantic Oceanographic and Meterological Laboratory. Atlantic Oceanographic and Meteorological Laboratory (AOML) South Florida Program Moored Instrument Array. (2009).
21.
National Oceanic and Atmospheric Administration (NOAA); National Data Buoy Center. National Data Buoy Center. (2024).
22.
U.S. Geological Survey (USGS). National Water Information System. (2024).
23.
Florida International University; National Oceanic and Atmospheric Administration (NOAA); National Marine Sanctuaries Program. Florida Keys National Marine Sanctuary Seagrass Monitoring Project. (2021).
24.
Florida Fish and Wildlife Conservation Commision (FWC); Florida Wildlife Research Institute (FWRI). Water Temperature on Coral Reefs in the Florida Keys. (2022).
25.
Florida Keys National Marine Sanctuary (FKNMS). Continuous Bottom Temperature Measurements along the Florida Reef Tract. (2014).
26.
Florida Department of Environmental Protection (DEP); Office of Resilience and Coastal Protection (RCP); Florida Keys Aquatic Preserves. Florida Keys Aquatic Preserves Continuous Water Quality Monitoring. (2024).
27.
Miami-Dade County Division of Environmental Resources Management (DERM). Miami-Dade County DERM Benthic Habitat Monitoring Program. (2023).